1. Technical Field
The present invention relates to a honeycomb structure and, more specifically, relates to a honeycomb structure which functions not only as a catalyst carrier, but also as a heater by applying a voltage and which can suppress bias of a temperature distribution when the voltage is applied.
2. Description of Related Art
Conventionally, a cordierite honeycomb structure having a catalyst loaded thereon has been used for treating harmful substances in exhaust gas discharged from an automobile engine. It is known that a honeycomb structure formed of a silicon carbide based sintered body is used for purifying exhaust gas (see, e.g., Patent Document 1).
In the case of treating exhaust gas by a catalyst loaded on a honeycomb structure, it is necessary to raise temperature of the catalyst up to predetermined temperature. However, since catalyst temperature is low upon engine start-up, there was a problem of insufficient purification of exhaust gas.
Therefore, there is studied a method for raising temperature of exhaust gas by disposing a metal heater on the upstream side of a honeycomb structure having a catalyst loaded thereon (see, e.g., Patent Document 2).